cody Posted August 17, 2007 Share Posted August 17, 2007 Hello,i'm new to the forum so hello to all.I've got a project bike,81 maxxim 550.When i got the bike the carbs where totally gummed up.Other than that it seemed to be in pretty good shape.The previous owner said the bike ran great but he let it sit for a year and it would not start.He is my friend and i believe him about it running great.I have cleaned the carbs 7 times and think they have got to be clean by now.I even let them soak in parts cleaner for a day this last time.I used small copper wire to clean all jets and passege way that i can get to.I also have used compressed air and carb cleaner each time.I hear air come through all passege ways so i think i got them all clear. I can start the bike but the rt exhaust pipe doesn't get very hot so it must not be firing much or at all.I have spark and fuel in the carb.When i take it for a test ride the bike has a lot off power when you twist the throtle but you can here the cylinder not firing when you let off the throtle.When i come home the rt exhaust pipe it very hot so it must be firing when under a load. In the process of cleaning the carbs and trying to get it to run right i also adjusted the sync screws. I now know that probably was a mistake and it didn't change the problem anyway.I was trying anything at this point.When you listen to the exhaust i can here a cylinder want to fire every couple of seconds so i assume its the rt cylinder.All the others sound like they are firing correctly. I can't afford to take it to the yamaha dealer so i'm hoping some one can tell me where to go from here.I'm not a motor cycle mechanic so i'm at a loss as to where the problem could be.I have a spare parts bike and have tried changing the coil for that set of cylinders and it didn't help.I even swapping the coils and that didn't work either.I'm so frustrated but i won't give up trying to fix it.I love to ride.Maybe someone has had this problem or a similar problem a can help me.I just don't know what could cause this cylinder to not fire. Sorry this post is so long but i wanted to give all the info i could. Thank you, Cody. Link to comment Share on other sites More sharing options...
yoda Posted August 17, 2007 Share Posted August 17, 2007 Put new spark plugs in it and new Ht leads. This should cure the problem. Check the timing on both cylinders and balance the carbs. Ensure that the throttle slide is opening both butterflys to let air in. Let us know what happens. Link to comment Share on other sites More sharing options...
Moderator YamaHead Posted August 17, 2007 Moderator Share Posted August 17, 2007 Sounds like you definitely could use a Carb Synch! Although, this'll require a YICS shut-off tool to do it correctly You also might have a look @ the pick-up coils located on the left end of the crank. Make sure they're clean as they send the initial signal to the primary coils. Best of Luck with it-- BTW..... to the forum Link to comment Share on other sites More sharing options...
cody Posted August 18, 2007 Author Share Posted August 18, 2007 Thanks for your replies.I checked out the pickup coil assembly and it look like brandnew,never been touched from the factory.There are 2 pickups,the bottom one look as if it is a little worn but the top looks like its brand new.I don't know what you call the piece that spins around but is it supposed to touch the brass points on the coil or just be very close as it comes by it?As the (plate?) comes by the bottom coil it is super close to it but the top one has at least a full 1/16 of a gap when the plate comes by it which explains why it looks perfect.How close should the gap be and can you adjust them to change the gap?I'm sure this is a stupid question but i don't want to make a new problem to my bike. Thanks cody. Link to comment Share on other sites More sharing options...
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